本文整理汇总了C++中module::global_iterator::use_empty方法的典型用法代码示例。如果您正苦于以下问题：C++ global_iterator::use_empty方法的具体用法？C++ global_iterator::use_empty怎么用？C++ global_iterator::use_empty使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类module::global_iterator的用法示例。
在下文中一共展示了global_iterator::use_empty方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: OptimizeGlobals
/// OptimizeGlobals - This method uses information taken from DSA to optimize
/// global variables.
///
bool DSOpt::OptimizeGlobals(Module &M) {
DSGraph* GG = TD->getGlobalsGraph();
const DSGraph::ScalarMapTy &SM = GG->getScalarMap();
bool Changed = false;
for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I)
if (!I->isDeclaration()) { // Loop over all of the non-external globals...
// Look up the node corresponding to this global, if it exists.
DSNode *GNode = 0;
DSGraph::ScalarMapTy::const_iterator SMI = SM.find(I);
if (SMI != SM.end()) GNode = SMI->second.getNode();
if (GNode == 0 && I->hasInternalLinkage()) {
// If there is no entry in the scalar map for this global, it was never
// referenced in the program. If it has internal linkage, that means we
// can delete it. We don't ACTUALLY want to delete the global, just
// remove anything that references the global: later passes will take
// care of nuking it.
if (!I->use_empty()) {
I->replaceAllUsesWith(ConstantPointerNull::get(I->getType()));
++NumGlobalsIsolated;
}
} else if (GNode && GNode->NodeType.isCompleteNode()) {
// If the node has not been read or written, and it is not externally
// visible, kill any references to it so it can be DCE'd.
if (!GNode->NodeType.isModifiedNode() && !GNode->NodeType.isReadNode() &&I->hasInternalLinkage()){
if (!I->use_empty()) {
I->replaceAllUsesWith(ConstantPointerNull::get(I->getType()));
++NumGlobalsIsolated;
}
}
// We expect that there will almost always be a node for this global.
// If there is, and the node doesn't have the M bit set, we can set the
// 'constant' bit on the global.
if (!GNode->NodeType.isModifiedNode() && !I->isConstant()) {
I->setConstant(true);
++NumGlobalsConstanted;
Changed = true;
}
}
}
return Changed;
}示例2: runOnModule
bool StripExternals::runOnModule(Module &M) {
bool Changed = false;
for (Module::iterator I = M.begin(); I != M.end(); ) {
if (I->hasAvailableExternallyLinkage()) {
assert(!I->isDeclaration()&&"Declarations can't be available_externally");
Changed = true;
++NumFunctions;
if (I->use_empty()) {
DEBUG(errs() << "Deleting function: " << *I);
Module::iterator todelete = I;
++I;
todelete->eraseFromParent();
continue;
} else {
I->deleteBody();
DEBUG(errs() << "Deleted function body: " << *I);
}
}
++I;
}
for (Module::global_iterator I = M.global_begin();
I != M.global_end(); ) {
if (I->hasAvailableExternallyLinkage()) {
assert(!I->isDeclaration()&&"Declarations can't be available_externally");
Changed = true;
++NumVariables;
if (I->use_empty()) {
DEBUG(errs() << "Deleting global: " << *I);
Module::global_iterator todelete = I;
++I;
todelete->eraseFromParent();
continue;
} else {
I->setInitializer(0);
I->setLinkage(GlobalValue::ExternalLinkage);
DEBUG(errs() << "Deleted initializer: " << *I);
}
}
++I;
}
return Changed;
}